have done……since的一个问题谢谢网上有人说：have done for/since和have been doing for/since的区别如下：前者是完成时,表示动作结束了,后者是完成进行时,动作还在继续.但是我看吸血鬼日记时看到吸

have done……since的一个问题谢谢网上有人说：have done for/since和have been doing for/since的区别如下：前者是完成时,表示动作结束了,后者是完成进行时,动作还在继续.但是我看吸血鬼日记时看到吸 have done……since的一个问题谢谢网上有人说：have done for/since和have been doing for/since的区别如下：前者是完成时,表示动作结束了,后者是完成进行时,动作还在继续.但是我看吸血鬼日记时看到吸 since前用have done 还是have been done have done……when 的句型? 问几个短语的区别could have donemight have done should have done since we have done our homework now对吗 What have you done since you returned to China? may have done和may have done 的区别RTmay have done和might have done done,tobe done,to have been done,to have done,having done,having been done的区别还有用法?救我……RT,还有啥时候用to be done,啥时候用todo?如There is a lot of work to do.为什么不用to be done?With a lot of work to do,he went ou make done和have done有什么区别么?记得看过一个例句是Did I make myself understood?其中用到的词组是make……done,就想起来以前背过的词组have……done,请问这两个词组有区别么?区别是什么呢?万分感激 have done 与其 had done 的区别 was/were done 和 have done 的区别最好各自有一个例句 have .since did区别have .since have done?eg：I haven’t seen you since I’ve been back.I haven’t seen you since I was back. We have since confirmed that……中“since”的意思和用法是什么?We have since confirmed that……这个句型中,“since”的意思和用法是什么? 求问一个有关时态的初中英语题：have done/have been doing我记得在以前的题里,have done和have been having都是可以通用、互换的.但是这次考试遇上了这么一个题We ____(have) it for a long time.（我们已经拥 被动语态be done中 be是什么词性?还有现在完成时的被动语态have been done 中have been是什么词性?是助动词系动词还是…… shouldn't have done couldn'd have done should have done could have done 他们的意思到底 实际有没有做就是比如说第一个的意思 到底实际上有没有做很纠结啊 have ever done 与 have never done的区别